Method and apparatus for measuring temperature within a given temperature range using a selected temperature sensor

ABSTRACT

A device provides a temperature control and/or monitoring, including a controller to receive a minimum temperature value and a maximum temperature value of a temperature range to be measured. The controller correlates a known output signal range of a temperature sensor to the temperature range to be measured. Further, the controller receives an output signal from the temperature sensor, and generates a measured temperature value based on the output signal of the temperature sensor. A method to control and/or monitor a temperature is also provided.

TECHNICAL FIELD

The present disclosure relates generally to measuring temperature withina desired temperature range using a temperature sensor, and isparticularly pertinent for induction power sources used in weldingapplications.

BACKGROUND

An induction power source used in welding applications, such as theProHeat® 35 available from Miller Electric Manufacturing Co. (hereafter“ProHeat® 35”), provides induction heating for weld applicationsincluding pre-heating, stress relief, and post-weld heating. Forexample, providing heating to a workpiece can keep moisture out of aweld to mitigate hydrogen-induced cracking, prevent hot and cold spots,etc. To accommodate different parts and applications, the ProHeat® 35 isused with a number of accessories, including a rolling inductoraccessory having a rolling inductor (such as ProHeat® Rolling Inductoravailable from Miller Electric Manufacturing Co.) for providing uniformheat to moving parts.

FIG. 1 shows an example of an induction heating system 100 comprising,among others, an induction power source 102, a rolling inductor 104 viawhich heat is provided to a pipe 106, a thermocouple extension cable108, and a input power supply 110 supplying power to the induction powersource 102. In the system arrangement of FIG. 1, the thermocoupleextension cable 108 carries output signal(s) from one or morethermocouples that provide a temperature feedback used for temperaturecontrol and monitoring. For instance, the ProHeat® 35 currently providesup to six thermocouple inputs used by a built-in controller thatperforms temperature control and monitoring of the rolling inductor 104.

When using a rolling inductor, it can be difficult to measuretemperature at a location of the workpiece the rolling inductor isheating. Since a workpiece or the rolling inductor is moving, unlike inthe case of stationary parts, using a thermocouple in contact with theworkpiece does not produce accurate temperature readings. For example,in the arrangement of FIG. 1, a thermocouple welded to a given point onthe pipe rotates 360 degrees and measures the pipe temperature as it isheated and cooled, but only at one point. Controlling heat input fromthis point could result in overheating the pipe before the point andunder heating the pipe shortly after the point.

SUMMARY

One possible solution to the above-noted problem is to use another typeof a temperature sensor, such an infrared (IR) temperature sensor. Inthis regard, the IR temperature sensor can be mounted to the rollinginductor to measure a temperature very close to the point where therolling inductor is heating. However, there is a problem that wide rangeIR temperature sensors are sensitive to emissivity changes. There is aneed to calibrate for emissivity coefficients of the surfaces beingmeasured. This is particularly a problem with a surface that movesrelative to the sensor as the emissivity coefficient can change. Forexample, a rotating part can have low and high emissivity regions. IRtemperature sensors that are less sensitive to emissivity changes havelimited temperature ranges and often do not cover a heating range of agiven heating device, such as the ProHeat® 35.

In effect, selecting one particular IR sensor can limit a temperaturerange and an application for which a rolling inductor can be used.Therefore, what is needed is a way to use a desired temperature sensorwhile also covering a requisite temperature range of a givenapplication.

The present disclosure provides an adjustable temperature scale for atemperature sensor, giving a user an ability to select a temperaturesensor that has desired operational characteristics but also fits anapplication requiring a particular temperature range to be measured.

In an embodiment, a device providing a temperature control and/ormonitoring comprises (i) a controller and (ii) program logic held in adata storage and executable by the controller to cause the controller to(a) receive a minimum temperature value and a maximum temperature valueof a temperature range to be measured, (b) correlate a known outputsignal range of a temperature sensor to the temperature range to bemeasured, c) receive an output signal from the temperature sensor, and(d) generate a measured temperature value based on the output signal ofthe temperature sensor.

In an embodiment, the program logic further causes the controller tocontrol or monitor temperature with respect to a part whose temperatureis being measured using the measured temperature value.

In an embodiment, the program logic further causes the controller todisplay the measured temperature value to a user.

In an embodiment, the temperature sensor is an infrared (IR) temperaturesensor.

In an embodiment, the temperature sensor is interconnected with thedevice via an input interface.

In an embodiment: (a) the output signal is a current signal, and (b) theinput interface carries the output signal converted to a voltage signalvia a biasing resistor.

In an embodiment: (a) the device further comprises one or moretemperature sensor inputs for receiving inputs from a temperature sensorof a first temperature sensor type, (b) the temperature sensor is of asecond temperature sensor type different from the first temperaturesensor type, and (c) the output signal range of the temperature sensorreceived via the one or more temperature sensor inputs is different froman output signal range of the temperature sensor of the firsttemperature sensor type received via the one or more temperature sensorinputs such that the two output signal ranges do not overlap.

In an embodiment, the program logic causes the controller to correlate aminimum output signal of the temperature sensor to the minimumtemperature value and correlate a maximum output signal of thetemperature sensor to the maximum temperature value.

In an embodiment, the program logic causes the controller to correlatethe known output signal range of the temperature sensor to thetemperature range to be measured using a linear scale.

In an embodiment, the linear scale follows the following relationship:Temp=(((AD__(RawInput) −I _(AD_RawMin))*(T__(MaxTemp)−T__(MinTemp)))/((I _(AD_RawMax) −I__(RawMin))))+T_where,

T__(MinTemp) and T__(MaxTemp) are the minimum and maximum temperaturevalues, respectively, and

I_(AD_RawMin) and I_(AD_RawMax) are analog-to-digital (A/D) valuescorresponding to minimum and maximum output current signals of thetemperature sensor, respectively.

In an embodiment: (a) the device further comprises an A/D converter, and(b) the A/D values are computed as follows:AD_RawInput=((I__(Output) *R__(Bias)*2{circumflex over( )}^(Scale)*Gain))/V_ref,where,

I__(Output) is a current output signal,

R__(Bias) is a value of a biasing resistor for conversion of the currentoutput signal to an output voltage signal to be input to an A/Dconverter, and

Scale, Gain, and V_ref are values of N for an N-bit converter, A/D gain,and reference voltage for the A/D converter, respectively.

In an embodiment, a temperature affecting device is controlled based atleast in part on the expressed measured temperature value.

In an embodiment, the output signal is a voltage signal, the voltage ofwhich correlates to the measured temperature value.

In an embodiment, the output signal is a current signal, the amperage ofwhich correlates to the measured temperature value.

In an embodiment, the output signal is a digital signal, the pulse widthor numerical value of which correlates to the measure temperature value.

In an embodiment, a method for use with a device providing a temperaturecontrol and/or monitoring comprises (i) receiving, via a controller, aminimum temperature value and a maximum temperature value of atemperature range to be measured, (ii) correlating, via the controller,a known output signal range of a temperature sensor to the temperaturerange to be measured, (iii) receiving, via the controller, an outputsignal from the temperature sensor, and (iv) generating via thecontroller, a measured temperature value based on the output signal ofthe temperature sensor. In one example, the temperature sensor is an IRtemperature sensor and the measured temperature value is expressed as anelectrical signal.

In an embodiment, the measured temperature value is used by thecontroller to control or monitor temperature with respect to a partwhose temperature is being measured.

In an embodiment, the measured temperature value in the form of atemperature reading is provided by the controller for display to a user.

Additional features and advantages of embodiments will be set forth inthe description, which follows, and in part will be apparent from thedescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure can be better understood by referring to thefollowing figures. The components in the figures are not necessarily toscale, emphasis instead being placed upon illustrating the principles ofthe disclosure. In the figures, reference numerals designatecorresponding parts throughout the different views.

FIG. 1 illustrates a heating system including an induction power sourceand a rolling inductor system;

FIG. 2 is a simplified block diagram of a system in which theillustrative embodiment can be carried out;

FIG. 3 is a flow chart showing an exemplary set of functions that can becarried out using the system of FIG. 2;

FIG. 4 illustrates one example arrangement showing an interconnection ofan IR temperature sensor to a heating power source;

FIGS. 5A and 5B show examples of screen views during a user setupconfiguration of a heating power source;

FIG. 6 illustrates one example a processing system in accordance withthe illustrative embodiment.

FIG. 7 illustrates an arrangement in which an IR temperature sensor ismounted to a rolling inductor.

DETAILED DESCRIPTION

The present disclosure is herein described in detail with reference toembodiments illustrated in the drawings, which form a part hereof. Otherembodiments may be used and/or other changes may be made withoutdeparting from the spirit or scope of the present disclosure. Theillustrative embodiments described in the detailed description are notmeant to be limiting of the subject matter presented herein.

Reference will now be made to the exemplary embodiments illustrated inthe drawings, and specific language will be used herein to describe thesame. It will nevertheless be understood that no limitation of the scopeof the invention is thereby intended. Alterations and furthermodifications of the inventive features illustrated herein, andadditional applications of the principles of the inventions asillustrated herein, which would occur to one skilled in the relevant artand having possession of this disclosure, are to be considered withinthe scope of the present disclosure.

FIG. 2 depicts a simplified block diagram of a system 100 in which anillustrative embodiment of the present invention can be carried out. Asshown in FIG. 2, the system 200 comprises a heating power source 202coupled with a temperature sensor 204. As shown in FIG. 2, the heatingpower source 202 includes a controller 206. Although not illustrated,the temperature sensor 204 and the controller 206 may be interconnectedvia a suitable input interface located externally or internally to thecontroller 206. In the illustrative embodiment, the heating power source202 preferably is an induction power source, such as the ProHeat® 35. Onthe other hand, the temperature sensor 204 preferably is an IRtemperature sensor. One example of a suitable IR temperature sensor isan IR sensor with a narrow temperature range but good emissivitysensitivity (i.e., less affected by emissivity differences), preferrablya programmable sensitivity. Such an IR sensor preferably outputs acurrent signal in a range of 4-20 mA, and the sensitivity can beprogrammed to limit reading errors to within plus or minus 25 degreesFahrenheit. Such a sensor can have a 2 micron optical filter range.However, in alternative embodiments, another heating power source and/ortemperature sensor may be used instead.

As a general matter, in accordance with the illustrative embodiment, thecontroller 206 is configured to correlate a range of an output signal(or “output signal range,” for short) of the temperature sensor 204 to adesired temperature range to be measured, such as a temperature rangeselected by a user. In this regard, the controller 206 is then able todetermine a current temperature within that temperature range based onan output signal of the temperature sensor 204 received by the heatingpower source 202.

FIG. 3 is a flow chart summarizing an example set of functions thatcould be carried out in accordance with the arrangement of FIG. 2, forinstance. At step 302, the controller 206 receives a minimum temperaturevalue and a maximum temperature value of a temperature range to bemeasured. At step 302, the controller 206 correlates a known outputsignal range of a temperature sensor to the temperature range. At step304, the controller 206 receives an output signal from the temperaturesensor. At step 306, the controller generates a measured temperaturevalue based on the output signal of the temperature sensor.

The measured temperature value can be expressed in a number of differentways, but typically is some type of electrical signal. One example is avoltage signal the voltage of which varies in accordance with andcorrelates to the measured temperature value. Another example is acurrent signal the amperage of which varies and correlates to themeasured temperature value. Yet another example is a digital signal thepulse width (if only a single pulse), pulse count (if multiple pulses)or numerical value (if using a system such as an ASCII or a power basedsystem) of which varies and correlates to the measured temperaturevalue.

The electrical signal in turn can be used to control a temperatureaffecting device such as the power source 202, the power output of whichcan be controlled to affect the heat applied to the measured point(s).

In accordance with the illustrative embodiment, the controller 206executes program logic to carry out various functions described herein,such as those in FIG. 2 for instance. The program logic may define analgorithm configured to correlate the output signal range of thetemperature sensor 204 to a predetermined temperature range. In theillustrative embodiment, the algorithm is configured such that a minimumoutput signal value of the temperature sensor 204 corresponds to aminimum temperature value of the predetermined temperature range and amaximum output signal value of the temperature sensor 204 corresponds toa minimum temperature value of the predetermined temperature range. Inthis regard, the algorithm creates a linear scale that provides a linearrelationship between an output signal within the output signal range ofthe temperature sensor 204 and a temperature within the predeterminedtemperature range. This way, temperature values within the predeterminedtemperature range can be generated by the controller 206 based on anoutput signal of the temperature sensor 204.

In the illustrative embodiment, the temperature sensor 204 outputs acurrent signal. In one example, the output current signal is in apreferred range of 4-20 mA. Further, the algorithm is configured tocorrelate the output signal range of the temperature sensor 204 to apredetermined temperature range according to the following formula:Temp=(((AD__(RawInput) −I _(AD_RawMin))*(T__(MaxTemp) −T__(MinTemp)))/((I _(AD_RawMax) −I_ _(RawMin))))+T__(MinTemp)  Equation(1)where,

T__(MinTemp) and T__(MaxTemp) are minimum and maximum temperatureinputs, respectively, and

I_(AD_RawMin) and I_(AD_RawMax) are analog-to-digital (A/D) valuescorresponding to minimum and maximum output current signals of atemperature sensor, respectively.

The A/D values are associated with an A/D converter of the heating powersource 202 and are computed according to the following formula:AD_RawInput=((I__(Output) *R__(Bias)*2{circumflex over( )}^(Scale)*Gain))/V_ref  Equation (2)where,

I__(Output) is a current output signal,

R__(Bias) is a value of a biasing resistor for conversion of the currentoutput signal to an output voltage signal to be input to the A/Dconverter, and

Scale, Gain, and V_ref are values of N for an N-bit converter, A/D gain,and reference voltage for the A/D converter, respectively.

As can be seen from the above Equation (1), the sensor output signalrange is correlated to a temperature range defined by the minimum andmaximum temperature inputs such that the minimum value of the outputcurrent signal of the temperature sensor 204 corresponds to the minimumtemperature input. On the other hand, the maximum value of the outputcurrent signal of the temperature sensor 204 corresponds to the maximumtemperature input. Measured temperature values corresponding to thesensor's output current signals are generated using a linear scale setup based on the minimum and maximum temperature inputs.

The measured temperature value may be subsequently used by thecontroller 202 in the form of a digital or analog signal to performother functions such as temperature control and/or monitoring. In oneexample, the controller 202 may use a signal indicative of the measuredtemperature value as a feedback in controlling heating and cooling of apart to which a heat is applied, such as via a rolling inductor.

The control of heating or cooling can be effected by controlling theapplication of a signal to the rolling inductor or another heat source.In another example, the controller 202 may use such a signal to monitora temperature at a given point (e.g., on a workpiece) to ensure that themeasured temperature is at a desired level. In yet another example, thecontroller 202 may send the signal indicative of the measuredtemperature value to be displayed to a user as a temperature reading ona display of the heating power source 202. Other examples may bepossible as well.

In the present example, the temperature sensor output is in the form ofa current signal, such as in the range of 4 mA to 20 mA. In this case,the output current signal is converted to a voltage signal for input toan A/D converter associated with the heating power source 202 via abiasing resistor (or “R__(Bias)” in the Equation (2)). The biasingresistor sets a voltage range to be input to an A/D converter of theheating power source 202. The A/D values are, in turn, used to compute acurrent temperature value from a current temperature sensor input to theheating power source 202.

To illustrate, in the case of the ProHeat® 35 and IR temperature sensorwith a 4-20 mA output range, the biasing resistor is preferably a 20 ohmresistor that sets a voltage range of 80 mV to 400 mV to be input to A/Dconverter of the ProHeat® 35. For this input voltage range, in the aboveEquation (2), the values for the gain G, voltage reference V_Ref, andScale parameters for the ProHeat A/D converter are 4, 18, and 2.048 VDC, respectively. The A/D input values are, in turn, used in Equation(1) to compute a current temperature value from a current temperaturesensor input to the heating power source 202.

It should be noted, however, the above example is provided forillustrative purposes only, and one skilled in the art will appreciatethat the above equations could be used and/or modified accordingly toaccommodate temperature sensors with other output signal ranges andheating power sources having different operational characteristics fromthose provided above.

It is also noted that the term “output signal” of the sensor as usedherein, refers not only to the signal directly output from the sensor,but also a converted version of the signal, unless specifically notedotherwise. Both are directly correlated to the sensed temperature andthus indicative of the temperature.

FIG. 4 illustrates one exemplary arrangement 400 showing aninterconnection of an IR temperature sensor 402 to a heating powersource 404. More specifically, as shown in FIG. 4, the IR temperaturesensor 402 is interconnected to the heating power source 404 via aninput interface 406. As shown in FIG. 3, in this example arrangement,the heating power source 404 is the ProHeat® 35. The, input interface406 could be internal or external to the heating power source 404.

In the arrangement of FIG. 4, an analog output signal from the IRtemperature sensor 402 is supplied to IR sensor inputs “RC1-D” and“RC1-E” on the input interface 406. For example, an IR sensor, providesanalog output wires via which the sensor can be connected to acontroller with the 24 V DC power supply. As such, as shown in FIG. 3,the 24 VDC and COM (aka “common”) outputs on the heating power source404 can be connected to power IR sensor inputs on the input interface406 (e.g., “RC1-A” and “RC1-B” inputs) to power up the IR sensor with 24V DC. On the other hand, the sensor output signal is converted to avoltage signal using a biasing resistor 408 (e.g., a 20 ohm resistor).The voltage signal, together with a ground lead for the IR sensor 402,coming out of IR sensor outputs on the input interface 406 is, in turn,fed into respective thermocouple inputs (e.g., “TC1” inputs representingpositive, negative, and ground terminals) on the heating power source404.

In one embodiment, the input interface 404 may be in the form of a boardor a sheet metal carrying wire connectors interconnecting the IR inputsand IR outputs. However, the input interface may take other forms aswell (e.g., a connection box). Additionally, although FIG. 4 shows theinput interface being external to the heating power source 404, it maybe possible to integrate such input interface with the heating powersource 404, such as the ProHeat® 35. Further, as shown in FIG. 4, thebiasing resistor 408 may be installed at the end of an IR temperaturesensor cable at the input interface 406.

Further, although a hard-wired connection arrangement is discussedabove, the sensor and controller could be connected by means of wirelesscommunications. Such communications could be of any suitable type, suchas, to name a few, a proprietary radio communications protocol, any ofthe Bluetooth® protocols or any of the IEEE wireless protocols. Theoutput signal could be in an analog or digital format. The key is forthe output signal to have a known range, and the controller to implementa scale to convert that range into a new range useable by thecontroller.

The following description will now describe one example application thatmay be carried out using the arrangement 400.

With the arrangement 400, in one embodiment, the heating power source404 may be configured with a setup option that allows a user to enableIR temperature sensing on thermal couple channels of the heating powersource 404. As such, when the IR sensor 402 is connected to the heatingpower source 404, an A/D gain for thermocouple channels may beautomatically changed from a thermocouple range (e.g., K-typethermocouple range) to the IR input range, such as the 80-400 mV inputrange for the IR sensor 402 with an output of 4-20 mA and the biasingresistor 408 of 20Ω. Further, the setup option may allow the user toenter a minimum temperature setting and a maximum temperature setting.

FIG. 5A shows an example of a system setup screen on a display of theheating power source 404. To view this screen, the user maysimultaneously press the “Parameters” and “Program” buttons. Bysimultaneously pressing the “Parameters” and “Program” buttons a secondtime an example screen shown in FIG. 5B will appear on the display ofthe heating power source 404. The user can then use the “Cursor” and“Increase/Decrease buttons” to set desired input parameters. Forinstance, the user can adjust “IR Input Max” and/or “IR Input Min”temperature setting to change a selected temperature range to bemeasured.

When the “TC1,2 Type . . . :” parameter shown in FIG. 5B is set toIR4-20, the heating power source 404 will look for an IR signal voltageequivalent to 4-20 mA current dropped across a 20 ohm resistor. In apreferred embodiment, the resulting input signal voltage is above thetype-K thermocouple voltage so that there is no overlap between an inputsignal range associated with a thermocouple temperature sensor and an IRtemperature sensor.

Effectively, by setting the IR input signal range (e.g., an inputvoltage range) to the heating power source 404 to be different from aninput signal range associated with another type of a temperature sensingdevice that can be connected to the heating power source 404, one caneliminate a potential problem of a users connecting a wrong device andseeing a signal reading that is inaccurate.

In the present example, the “IR Input Min” and “IR Input Max”temperature settings establish the IR sensor's minimum and maximumtemperature readings that are correlated to the 4-20 mA output signal.As such, a 4 mA output signal corresponds to a temperature reading of212 degrees F. while a 20 mA output signal corresponds to a temperaturereading of 750 degrees F.

Further, preferably, the Min and Max target temperatures set on theheating power source 404 are respectively 5 degrees C. above a minimumtemperature for which the IR temperature sensor 402 is rated for and 5degrees C. less than a maximum temperature for which the IR temperaturesensor 402 is rated for. This ensures a certain margin within which theheating power source 404 can work to control heating at the top andbottom of a specified temperature range of the IR sensor 402.

Note that, although FIGS. 2-5B describe one illustrative embodiment ofthe present disclosure, variations are possible.

For example, a heating power source may be configured to automaticallyset a temperature range based on a particular type of a temperaturesensor that is connected to the heating power source. The sensor typemay be set by a user. For example, the heating power source may beconfigured with a user sensor-selection menu, allowing a user to selecta particular temperature sensors out of different sensor options.

Alternatively, using current technology, the sensor could be tagged withan identification using an RFID tag or a machine readable code such as abar code. The heating power source would have a suitable reader for theidentification tagging such as an RFID reader or barcode reader to readin the type of sensor information, and then choose the protocol to beemployed for use with the sensor.

Alternatively, the sensor type may be determined by the heating powersource.

In this regard, the heating power source may determine the sensor typeby using a digital or analog output of the temperature sensor. In oneembodiment, the heating power source is configured by programming torecognize whether a type-K thermocouple or IR sensor is physicallyconnected to the heating power source. In the embodiment, the controllerdetects the input voltage and then executes the protocol associated withthe detected input device. That is to say, if the input voltage is belowa predetermined voltage, the controller determines that the input deviceis a type-K thermocouple, otherwise the input device is determined to bean IR sensor. Alternatively, if the input voltage is above apredetermined threshold, the controller determines that the input deviceis an IR sensor, otherwise the input device is determined to be a type-Kthermocouple. Alternatively, if the input voltage is above apredetermined threshold, the controller determines that the input deviceis an IR sensor, but if the input voltage is below a predeterminedthreshold is below another predetermined threshold the controllerdetermines that the input device is a type-K thermocouple, otherwise theinput device is not recognized and an error is indicated. As yet anotheralternative, the controller can be programmed to look for input voltagesor currents within predetermined ranges, so that if the input voltagefalls within a first predetermined range, the controller recognizes theinput device as a type-K thermocouple, if the input voltage falls withina second predetermined range, the controller recognizes the input deviceas an IR sensor, but if the input voltage falls outside of anypredetermined range, the input device is not recognized and thecontroller notifies the operator as appropriate.

Although an IR temperature sensor with an output in the form of acurrent signal has been described above, IR temperature sensors with adifferent type of a signal output (e.g., a voltage signal) may be usedinstead. Similarly, IR temperature sensors having an output signal rangeother than a 4-20 mA range may be used instead (e.g., 0-20 mA, 0-10V,etc.). One skilled in the art will appreciate that a control algorithmas described above can be established/modified accordingly toaccommodate different types of signals and/or output signal ranges.

Although arrangements utilizing only one temperature sensor have beendescribed above, the control principles of the present disclosure can bemodified for a different number of temperature sensors and/ortemperature sensing inputs. However, the heating power source (e.g., theProHeat® 35) can also be configured to use only one temperature sensortype and a set temperature range.

In other embodiments, an IR sensor may be replaced by anothertemperature sensing technology such as a thermocouple (e.g., a K-typethermocouple), thermistor, or a bolometer type device. For example, thecontrol principles of the present disclosure can be modified to convertIR temperature sensor output to a K-type thermocouple output.

In accordance with the illustrative embodiment, various functionsdescribed herein could be carried out by a processing system 500,example of which is shown in FIG. 6. The processing system 500 includesat least one processor 502 and memory 504, coupled together via a bus506. The processing system 80 may be, for example, incorporated in thecontroller 206 or its components may be distributed across thecontroller 206 and other element(s) of the heating power source 202. Forexample, the memory 504 may be external to the controller 206. Variousexamples are possible.

In one embodiment, the processor(s) 502 may be dedicated processor(s) orgeneral purpose processor(s) configured to execute computer-readableprogram code. The memory 504 may be volatile or non-volatile nontransitory computer-readable medium or media, now known or laterdeveloped. The memory 504 may hold program logic comprising programinstructions 508 (e.g., machine language instructions) executable by theprocessor(s) 502 to carry out various functions described herein. Inthis regard, the program logic held in the memory 504 will preferablydefine an algorithm configured to correlate the output signal range ofthe temperature sensor 204 to a predetermined temperature range asdescribed above.

Additionally, the memory 504 may also store any other data, such as dataused by the processor(s) 502 in the execution of the programinstructions 508. However, any additional data may also be held in otherdata storage location(s) separate from the memory 504.

Further, although not shown in FIG. 6, the processing system 500 mayinclude a number of interfaces, such as user interface(s) (e.g., userprogramming interface), communication interface(s) (e.g., an interfacefor communicating data to/from the memory 504 related to a temperatureoutput signal), and/or the like. Also, other elements (e.g., modules,input lines, buses, etc.) may be included as well.

Advantageously, with a benefit of the present disclosure, a user can usea heating power source or any other device providing a temperaturecontrol and/or monitoring with a range of different temperature sensorsto measure temperatures within a temperature range required by a givenapplication, even if a desired temperature sensor has a limitedtemperature range. Further, in the context of an induction power sourcesuch as the ProHeat® 35, the present disclosure provides a way tomeasure temperature with respect to a heating systems using movingparts, such as a rolling inductor and a pipe and/or flat surface.

To illustrate, FIG. 7 shows an arrangement 600 in which an IRtemperature sensor 602 is mounted to a rolling inductor 604. As notedabove, IR sensors often do not cover a heating range of a given heatingdevice (e.g., the ProHeat® 35). However, with the methods describedherein, it is possible to use the IR temperature sensor 602 to measuresubstantially precisely a temperature within an area where the rollinginductor 604 is heating, such a particular area on a workpiece, such asa pipe 606.

While various aspects and embodiments have been disclosed, other aspectsand embodiments are contemplated. The various aspects and embodimentsdisclosed are for purposes of illustration and are not intended to belimiting, with the true scope and spirit being indicated by thefollowing claims.

The foregoing method descriptions and the process flow diagrams areprovided merely as illustrative examples and are not intended to requireor imply that the steps of the various embodiments must be performed inthe order presented. As will be appreciated by one of skill in the artthe steps in the foregoing embodiments may be performed in any order.Words such as “then,” “next,” etc. are not intended to limit the orderof the steps; these words are simply used to guide the reader throughthe description of the methods. Although process flow diagrams maydescribe the operations as a sequential process, many of the operationscan be performed in parallel or concurrently. In addition, the order ofthe operations may be re-arranged. A process may correspond to a method,a function, a procedure, a subroutine, a subprogram, etc. When a processcorresponds to a function, its termination may correspond to a return ofthe function to the calling function or the main function.

Further, while the invention has been described mainly in connectionwith an induction heater for welding purposes, it has broaderapplicability, including, but not limited to, welding power supplies,cutting power supplies, and liquid cooled heating cables. Further, thesensors can be handheld or fixtured.

The various illustrative logical blocks, modules, circuits, andalgorithm steps described in connection with the embodiments disclosedhere may be implemented as electronic hardware, computer software, orcombinations of both. To clearly illustrate this interchangeability ofhardware and software, various illustrative components, blocks, modules,circuits, and steps have been described above generally in terms oftheir functionality. Whether such functionality is implemented ashardware or software depends upon the particular application and designconstraints imposed on the overall system. Those of ordinary skill inthe art may implement the described functionality in varying ways foreach particular application, but such implementation decisions shouldnot be interpreted as causing a departure from the scope of the presentinvention.

Embodiments implemented in computer software may be implemented insoftware, firmware, middleware, microcode, hardware descriptionlanguages, or any combination thereof. A code segment ormachine-executable instructions may represent a procedure, a function, asubprogram, a program, a routine, a subroutine, a module, a softwarepackage, a class, or any combination of instructions, data structures,or program statements. A code segment may be coupled to another codesegment or a hardware circuit by passing and/or receiving information,data, arguments, parameters, or memory contents. Information, arguments,parameters, data, etc. may be passed, forwarded, or transmitted via anysuitable means including memory sharing, message passing, token passing,network transmission, etc.

The actual software code or specialized control hardware used toimplement these systems and methods is not limiting of the invention.Thus, the operation and behavior of the systems and methods weredescribed without reference to the specific software code beingunderstood that software and control hardware can be designed toimplement the systems and methods based on the description here.

When implemented in software, the functions may be stored as one or moreinstructions or code on a non-transitory computer-readable orprocessor-readable storage medium. The steps of a method or algorithmdisclosed here may be embodied in a processor-executable software modulewhich may reside on a computer-readable or processor-readable storagemedium. A non-transitory computer-readable or processor-readable mediaincludes both computer storage media and tangible storage media thatfacilitate transfer of a computer program from one place to another. Anon-transitory processor-readable storage media may be any availablemedia that may be accessed by a computer. By way of example, and notlimitation, such non-transitory processor-readable media may compriseRAM, MRAM, ROM, EEPROM, CD-ROM or other optical disk storage, magneticdisk storage or other magnetic storage devices, or any other tangiblestorage medium that may be used to store desired program code in theform of instructions or data structures and that may be accessed by acomputer or processor. Disk and disc, as used here, include compact disc(CD), laser disc, optical disc, digital versatile disc (DVD), floppydisk, and Blu-ray disc where disks usually reproduce data magnetically,while discs reproduce data optically with lasers. Combinations of theabove should also be included within the scope of computer-readablemedia. Additionally, the operations of a method or algorithm may resideas one or any combination or set of codes and/or instructions on anon-transitory processor-readable medium and/or computer-readablemedium, which may be incorporated into a computer program product.

The preceding description of the disclosed embodiments is provided toenable any person skilled in the art to make or use the presentinvention. Various modifications to these embodiments will be readilyapparent to those skilled in the art, and the generic principles definedhere may be applied to other embodiments without departing from thespirit or scope of the invention. Thus, the present invention is notintended to be limited to the embodiments shown here but is to beaccorded the widest scope consistent with the following claims and theprinciples and novel features disclosed here.

What is claimed is:
 1. A method, comprising: providing a heating powersource with a controller that effects temperature control or temperaturemonitoring; receiving, via the controller, a first minimum temperaturevalue and a first maximum temperature value of a first temperature rangeto be measured; receiving, via the controller, a second minimumtemperature value and a second maximum temperature value of a secondtemperature range to be measured; correlating, via the controller, aknown first output signal range of a first temperature sensor of a firsttemperature sensor type to the first temperature range to be measured;correlating, via the controller, a known second output signal range of asecond temperature sensor of a second temperature sensor type differentfrom the first type to the temperature range to be measured to thesecond temperature range to be measured, wherein the first output signalrange of the first temperature sensor is different from the secondoutput signal range of the second temperature sensor such that the twooutput signal ranges do not overlap; receiving, via the controller, anoutput signal from the first temperature sensor or the secondtemperature sensor; determining, via the controller, whether the outputsignal is within the first output signal range or the second outputsignal range; generating, via the controller, a measured temperaturevalue based on the output signal of the first temperature sensor or thesecond temperature sensor; and adjusting, via the controller, an outputof the heating power source in response to the measured temperaturevalue.
 2. The method of claim 1, further comprising using, via thecontroller, the measured temperature value to control or monitortemperature with respect to a part whose temperature is being measured.3. The method of claim 1, further comprising providing, via thecontroller, the measured temperature value in the form of a temperaturereading for display to a user.
 4. The method of claim 1, wherein theoutput signal is a current signal.
 5. The method of claim 4, wherein thefirst known output signal range is 4-20 mA.
 6. The method of claim 4,wherein the current signal is converted to a voltage signal via abiasing resistor.
 7. The method of claim 1, wherein the output signal isa voltage signal.
 8. The method of claim 1, wherein the temperaturesensor is an infrared (IR) temperature sensor.
 9. The method of claim 1,wherein correlating, via the controller, the first known output signalrange of the first temperature sensor to the first temperature range tobe measured includes using a linear scale.
 10. The method of claim 9,wherein the linear scale follows the following relationship:Temp=(((AD__(RawInput) −I _(AD_RawMin))*(T__(MaxTemp)−T__(MinTemp)))/((I _(AD_RawMax) −I__(RawMin))))+T_ _(MinTemp), where,T__(MinTemp) and T__(MaxTemp) are the first minimum and first maximumtemperature values, respectively, and I_(AD_RawMin) and I_(AD_RawMax)are analog-to-digital (A/D) values corresponding to minimum and maximumoutput current signals of the first temperature sensor, respectively.11. The method of claim 10, wherein the A/D values are computed asfollows:AD_RawInput=((I__(Output) *R__(Bias)*2{circumflex over( )}^(Scale)*Gain))/V_ref, where, I__(Output) is a current outputsignal, R__(Bias) is a value of a biasing resistor for conversion of thecurrent output signal to an output voltage signal to be input to an A/Dconverter, and Scale, Gain, and V_ref are values of N for an N-bitconverter, A/D gain, and reference voltage for the A/D converter,respectively.
 12. The method of claim 1, wherein the heating powersource is an induction power source.
 13. The method of claim 1, whereinthe minimum temperature and maximum temperature values are selected by auser.
 14. A device, comprising: one or more temperature sensor inputsfor receiving inputs from a first temperature sensor of a firsttemperature sensor type and a second temperature sensor of a secondtemperature sensor type different from the first type, wherein a firstoutput signal range of the first temperature sensor is different from asecond output signal range of the second temperature sensor type suchthat the two output signal ranges do not overlap; a controller; programlogic held in a data storage and executable by the controller to causethe controller to: receive a first minimum temperature value and a firstmaximum temperature value of a first temperature range to be measured,correlate a known first output signal range of the first temperaturesensor to the first temperature range to be measured, receive a secondminimum temperature value and a second maximum temperature value of asecond temperature range to be measured, correlate a known second outputsignal range of the second temperature sensor to a second temperaturerange to be measured, receive an output signal from the firsttemperature sensor or the second temperature sensor, determine whetherthe output signal is within the first output signal range or the secondoutput signal range; generate a measured temperature value based on theoutput signal of the first temperature sensor or the second temperaturesensor; and a heating power source configured to adjust a heat output inresponse to the measured temperature value.
 15. The device of claim 14,wherein the program logic further causes the controller to control ormonitor temperature with respect to a part whose temperature is beingmeasured using the measured temperature value.
 16. The device of claim14, wherein the program logic further causes the controller to displaythe measured temperature value to a user.
 17. The device of claim 14,wherein the first temperature sensor type is an infrared (IR)temperature sensor and the second temperature sensor type is athermocouple.
 18. The device of claim 14, wherein the first and secondtemperature sensors are interconnected with the device via an inputinterface.
 19. The device of claim 18, wherein: the output signal is acurrent signal, and the input interface carries the output signalconverted to a voltage signal via a biasing resistor.
 20. The device ofclaim 14, wherein the program logic causes the controller to correlatethe known output signal range of the temperature sensor to thetemperature range to be measured using a linear scale.
 21. The device ofclaim 20, wherein the linear scale follows the following relationship:Temp=(((AD__(RawInput) −I _(AD_RawMin))*(T__(MaxTemp)−T__(MinTemp)))/((I _(AD_RawMax) −I__(RawMin))))+T_ _(MinTemp), where,T__(MinTemp) and T__(MaxTemp) are the minimum and maximum temperaturevalues, respectively, and I_(AD_RawMin) and I_(AD_RawMax) areanalog-to-digital (A/D) values corresponding to minimum and maximumoutput current signals of the temperature sensor, respectively.
 22. Thedevice of claim 21, wherein: the device further comprises an A/Dconverter, and the A/D values are computed as follows:AD_RawInput=((I__(Output) *R__(Bias)*2{circumflex over( )}^(Scale)*Gain))/V_ref, where, I__(Output) is a current outputsignal, R__(Bias) is a value of a biasing resistor for conversion of thecurrent output signal to an output voltage signal to be input to an A/Dconverter, and Scale, Gain, and V_ref are values of N for an N-bitconverter, A/D gain, and reference voltage for the A/D converter,respectively.
 23. The device of claim 14, wherein the device isconfigured to determine the sensor type from one of a digital or analogoutput of the first temperature sensor or the second temperature sensor.24. The device of claim 23, wherein the first temperature sensor type islocated at a first location on a workpiece and the second temperaturesensor type is located at a second location on the workpiece.
 25. Amethod, comprising: providing a device with a controller that effectstemperature control or temperature monitoring; receiving, via thecontroller, a minimum temperature value and a maximum temperature valueof a temperature range to be measured; correlating, via the controller,a known output signal range of a first temperature sensor of a firsttemperature sensor type to the temperature range to be measured using alinear scale or a second temperature sensor of a second temperaturesensor type different from the first type to the temperature range to bemeasured, wherein a first output signal range of the first temperaturesensor is different from a second output signal range of the secondtemperature sensor type such that the two output signal ranges do notoverlap; receiving, via the controller, an output signal from the firstor the second temperature sensor; determining, via the controller,whether the output signal is within the first output signal range or thesecond output signal range; generating, via the controller, a measuredtemperature value based on the output signal of the first or the secondtemperature sensor; wherein the linear scale follows the followingrelationship:Temp=(((AD__(RawInput) −I _(AD_RawMin))*(T__(MaxTemp)−T__(MinTemp)))/((I _(AD_RawMax) −I__(RawMin))))+T_ _(MinTemp), where,T__(MinTemp) and T__(MaxTemp) are the minimum and maximum temperaturevalues, respectively, and I_(AD_RawMin) and I_(AD_RawMax) areanalog-to-digital (A/D) values corresponding to minimum and maximumoutput current signals of the first or the second temperature sensor,respectively;AD_RawInput=((I__(Output) *R__(Bias)*2{circumflex over( )}^(Scale)*Gain))/V_ref, where, I__(Output) is a current outputsignal, R__(Bias) is a value of a biasing resistor for conversion of thecurrent output signal to an output voltage signal to be input to an A/Dconverter, and Scale, Gain, and V_ref are values of N for an N-bitconverter, A/D gain, and reference voltage for the A/D converter,respectively, and adjusting, via the controller, an output of a heatingpower source in response to measured temperature value.